NorCal Garden Musings and Know-How

A healthy, thriving lawn with no fertilizers?

I recently read Plenitude, a book by Juliet Schor. She came highly recommended by a fun financial blog I sometimes read – Mr. Money Mustache. Anyway, Schor is a leader of the Center for the New American Dream, and Plenitude is about living a more sustainable life, leaving behind the typical American consumerism, and basically redefining prosperity. There were quite a few great takeaways from the book, and one little gem is her mention of Harvard changing its landscape maintenance practices to eliminate chemical fertilizers and pesticides. They discovered how to feed the soil through reintroduction of fungi, bacteria and other microbes by using compost, compost tea, and other organic methods. See this great article in the New York Times about it. The article is from 2009, but it’s definitely relevant and very interesting.

Apparently, the grass before this change was only sending roots down 2-3″ and the soil was quite compacted from all the foot traffic. By creating a healthy soil biome, microbes loosened up the soil, and the grass now sends roots down 7-8″. The grass needs 30-50% less water, because the microbes produce water in their digestive processes and because the longer roots can access more of the water that’s already in the soil. The microbes now produce something like 150 lbs of nitrogen per acre, which eliminated the need to add nitrogen fertilizers to keep the grass green. This is all kind of amazing. Take a look at some of the information on Harvard’s website about this:

One of the interesting things I learned is that when we apply commercial salt-based fertilizers on our lawns, they actually kill the beneficial microbes that produce nitrogen. This leaves our lawn dependent on continued application of fertilizers, because the soil can’t produce its own nitrogen and needs ongoing supplementation. This is all very intriguing. I’m going to learn more and start using these techniques next year. Let’s see if I can stop using chemical fertilizers altogether!